2012 Annual Report
1a.Objectives (from AD-416):
Determine the ability of U.S. Army Fire Resistant Army Combat Uniform-P (FRACU-P), Type III, to retain permethrin and prevent insect bites at the required level.
1b.Approach (from AD-416):
This research will be conducted using the “bite protection” assay developed by MFRU/CMAVE to establish the level at which permethrin-treated Fire Resistant Army Combat Uniforms, Type III (FRACUs, Type III) prevent mosquito bites. The bite protection assay will be conducted on FRACU Type III uniforms by using human volunteers in an Institutional Review Board (IRB)-approved study protocol. Volunteers wear sewn sleeves of the uniform material to test if the garment prevents mosquito bites in a laboratory assay. The results are compared to an untreated control sleeve to determine the benefit of permethrin repellent as a function of the percentage reduction in bites compared to the control. Tests are conducted with uniform fabric that is treated prior to laundering, treated fabric washed 20 times and treated fabric washed 50 times. The 50 wash end point constitutes the expected lifetime of the uniform as a function of numbers of launderings. Studies are intended to be tested against multiple strains of mosquitoes to determine if the strain affects the outcome of the experiments. The final report is used by the United States Army to determine if a uniform supplier is meeting their specifications.
This project is conducted in support of in-house Objective 2, “Develop new application methods for pesticides to biting Nematocera,” and more specifically to sub-objective 2.A., “Determine factors that affect and enhance protection from insect bites through military and civilian repellent-treated clothing.”
Research efforts of the Natick Soldier Research, Development, and Engineering Center and the Mosquito and Fly Research Unit (MFRU) led to qualification of three vendors to supply the U.S. Army with permethrin-treated U.S. Army Combat Uniforms (ACUs). These uniforms are constructed of 50% nylon/50% cotton fibers. The bite protection levels of these factory-treated uniforms were very high (99-100% protection) even after uniforms had been washed through 50 cycles. A more durable Fire Resistant Army Combat Uniform (FRACU), type III was also evaluated after permethrin impregnation at the factory level. These uniforms provided at least 80% bite protection through 50 wash cycles. The final U.S. Army study completed was with the Fire Resistant Operation Enduring Freedom Camouflage (FROC) pattern. These uniforms are constructed of the FRACU, type III material, but with a seven color multicam pattern instead of the universal camouflage (digitized) pattern.
Progress was monitored and documented by reports issued to Natick at the completion of experiments and reporting of research results at international and national meetings and at committee meetings held at the Armed Forces Pest Management Board. An annual meeting to discuss annual research plans is held at the Natick Soldier Center at the start of each calendar year. Subordinate meetings on permethrin-treated uniforms are held during semi-annual meetings of the Armed Forces Pest Management Board on the campus of the Walter Reed Army Institute of Research.